<?php

/**
 * Created by PhpStorm.
 * User: Administrator
 * Date: 2019/8/20
 * Time: 10:40
 */
class 备份MySQL
{

}

define('MSB_VERSION', '1.0.0');

define('MSB_NL', "\r\n");

define('MSB_STRING', 0);
define('MSB_DOWNLOAD', 1);
define('MSB_SAVE', 2);
define('__SEP__', "/*sep*/" );

set_time_limit( 600 );

class MySQL_Backup {
    var $server = 'localhost';
    var $port = 3306;
    var $username = 'root';
    var $password = '';
    var $database = '';
    var $link_id = -1;
    var $connected = false;
    var $tables = array();
    var $drop_tables = true;
    var $struct_only = false;
    var $comments = true;
    var $backup_dir = '';
    var $fname_format = 'd_m_y__H_i_s';
    var $error = '';

    var $complete_inserts  = false;
    var $inserts_block     = 200;

    function Execute($task = MSB_STRING, $fname = '', $compress = false) {
        if ( !( $sql = $this->_Retrieve() ) ) {
            return false;
        }
        if ( $task == MSB_SAVE ) {
            if (empty($fname)) {
                $fname = $this->backup_dir;
                $fname .= date($this->fname_format);
                $fname .= ($compress ? '.sql.gz' : '.sql');
            }
            return $this->_SaveToFile($fname, $sql, $compress);
        } elseif ($task == MSB_DOWNLOAD) {
            if ( empty( $fname ) ) {
                $fname = date($this->fname_format);
                $fname .= ($compress ? '.sql.gz' : '.sql');
            }
            return $this->_DownloadFile($fname, $sql, $compress);
        } else {
            return $sql;
        }
    }

    function _Connect() {
        $value = false;
        if (!$this->connected) {
            $host = $this->server . ':' . $this->port;
            $this->link_id = mysql_connect($host, $this->username, $this->password);
        }
        if ($this->link_id) {
            if (empty($this->database)) {
                $value = true;
            } elseif ($this->link_id !== -1) {
                $value = mysql_select_db($this->database, $this->link_id);
            } else {
                $value = mysql_select_db($this->database);
            }
        }
        if (!$value) {
            $this->error = mysql_error();
        }
        return $value;
    }

    function _Query($sql) {
        if ($this->link_id !== -1) {
            $result = mysql_query($sql, $this->link_id);
        } else {
            $result = mysql_query($sql);
        }
        if (!$result) {
            $this->error = mysql_error();
        }
        return $result;
    }

    function _GetTables() {
        $value = array();
        if ( !( $result = $this->_Query('SHOW TABLES') ) ) {
            return false;
        }
        while ( $row = mysql_fetch_row( $result ) ) {
            if ( empty( $this->tables) || in_array( $row[0], $this->tables ) ) {
                $value[] = $row[0];
            }
        }
        if (!sizeof($value)) {
            $this->error = 'No tables found in database.';
            return false;
        }
        return $value;
    }

    function _DumpTable( $table ) {
        $value = '';
        $this->_Query( 'LOCK TABLES ' . $table . ' WRITE' );
        if ( $this->comments ) {
            $value .= '#' . MSB_NL;
            $value .= '# Table structure for table `' . $table . '`' . MSB_NL;
            $value .= '#' . MSB_NL . MSB_NL;
        }
        if ( $this->drop_tables ) {
            $value .= 'DROP TABLE IF EXISTS `' . $table . '`;' . __SEP__ . MSB_NL;
        }
        if ( !( $result = $this->_Query('SHOW CREATE TABLE ' . $table) ) ) {
            return false;
        }
        $row = mysql_fetch_assoc($result);
        $value .= str_replace("\n", MSB_NL, $row['Create Table']) . ';' . __SEP__;
        $value .= MSB_NL . MSB_NL;
        if (!$this->struct_only) {
            if ($this->comments) {
                $value .= '#' . MSB_NL;
                $value .= '# Dumping data for table `' . $table . '`' . MSB_NL;
                $value .= '#' . MSB_NL . MSB_NL;
            }
            $value .= $this->_GetInserts($table);
        }
        $value .= MSB_NL . MSB_NL;
        $this->_Query('UNLOCK TABLES');
        return $value;
    }

    function _GetInserts($table) {
        $value = '';
        if (!($result = $this->_Query('SELECT * FROM ' . $table))) {
            return false;
        }
        if ( $this->complete_inserts ) {
            while ($row = mysql_fetch_row($result)) {
                $values = '';
                foreach ($row as $data) {
                    $values .= '\'' . addslashes($data) . '\', ';
                }
                $values = substr($values, 0, -2);
                $value .= 'INSERT INTO ' . $table . ' VALUES (' . $values . ');' . __SEP__ . MSB_NL;
            }
        } else {
            $blocks_counter = 0;
            $blocks = array();
            while ($row = mysql_fetch_row($result)) {
                $values = array();
                foreach ($row as $data) {
                    $values[] = '\'' . addslashes($data) . '\'';
                }
                $blocks[] = '(' . implode( ',', $values ) . ')';

                if ( $blocks_counter < $this->inserts_block ) {
                    $blocks_counter++;
                } else {
                    $value .= 'INSERT INTO ' . $table . ' VALUES ' . implode( ',', $blocks ) . ";" . __SEP__ . MSB_NL;
                    $blocks = array();
                    $blocks_counter = 0;
                }
            }
            if ( count( $blocks ) ) {
                $value .= 'INSERT INTO ' . $table . ' VALUES ' . implode( ',', $blocks ) . ";" . __SEP__ . MSB_NL;
            }
        }
        return $value;
    }

    function _Retrieve() {
        $value = '';
        if (!$this->_Connect()) {
            return false;
        }
        if ($this->comments) {
            $value .= '#' . MSB_NL;
            $value .= '# MySQL database dump' . MSB_NL;
            $value .= '# Created by MySQL_Backup class, ver. ' . MSB_VERSION . MSB_NL;
            $value .= '#' . MSB_NL;
            $value .= '# Host: ' . $this->server . MSB_NL;
            $value .= '# Generated: ' . date('M j, Y') . ' at ' . date('H:i') . MSB_NL;
            $value .= '# MySQL version: ' . mysql_get_server_info() . MSB_NL;
            $value .= '# PHP version: ' . phpversion() . MSB_NL;
            if (!empty($this->database)) {
                $value .= '#' . MSB_NL;
                $value .= '# Database: `' . $this->database . '`' . MSB_NL;
            }
            $value .= '#' . MSB_NL . MSB_NL . MSB_NL;
        }
        if (!($tables = $this->_GetTables())) {
            return false;
        }
        foreach ($tables as $table) {
            if (!($table_dump = $this->_DumpTable($table))) {
                $this->error = mysql_error();
                return false;
            }
            $value .= $table_dump;
        }
        return $value;
    }

    function _SaveToFile($fname, $sql, $compress) {
        if ($compress) {
            if (!($zf = gzopen($fname, 'w9'))) {
                $this->error = 'Can\'t create the output file.';
                return false;
            }
            gzwrite($zf, $sql);
            gzclose($zf);
        } else {
            if (!($f = fopen($fname, 'w'))) {
                $this->error = 'Can\'t create the output file.';
                return false;
            }
            fwrite($f, $sql);
            fclose($f);
        }
        return true;
    }

    function _DownloadFile($fname, $sql, $compress) {
        header('Content-disposition: filename=' . $fname);
        header('Content-type: application/octetstream');
        header('Pragma: no-cache');
        header('Expires: 0');
        echo ($compress ? gzencode($sql) : $sql);
        return true;
    }
}